<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>原型链</title>
</head>
<body>
    
</body>
<script>
    function Add(a,b){
        return a+b
    }
    var add=new Add()
  Add.prototype={
      say:function(){
          return '我会说话'
      }
  }
    console.dir(add.constructor(2,4))
    console.dir(add)
</script>
</html>